The invention relates to a leveling, plumbing, and angular calibration instrument with a swinging suspended vertical body, which carries light elements and/or lenses and perhaps means for beam splitting and/or for converging light for the creation and emission of laser light with means to limit and/or block the swinging motion being allocated to the vertical body.
In various leveling, plumbing, and angular calibration instruments vertical bodies or plumb bobs are provided, which are suspended like a universal joint or via a ball joint. Sometimes the swinging motion is dampened by the use of magnets. Another known instrument provides for a plumb bob having a hemispherical clamping body in the proximity of the suspension site. Using a slide, a socket-like part must be moved upward to serve as a clamp. The common application of linear lasers is to project a horizontal and usually also a vertical line to the opposite wall, seen from the location of the instrument. An extraordinary application is characterized in that it is sufficient to show a 90° interface at an arbitrary height, i.e. no longer located in the horizontal line determined by the plumb bob. When in the known embodiment the vertical body is clamped with the hemispherical clamping body, while the instrument housing is positioned inclined, i.e. after the removal from a tripod or when being lifted off the ground, the vertical body in the instrument housing is also arranged in an inclined position. The axis of the vertical body is then no longer parallel to the exterior edge of the instrument housing. In spite of an expensive mechanism one important additional function is aggravated or has become impossible. This known instrument is even provided with an oscillation axis and with a guidance housing, but in spite thereof the user can project interfaces, i.e. intersections of a horizontal and a vertical line failing to intersect at precisely 90°. This potential source for errors is even more serious when slight deviations from 90° can no longer be safely detected by the naked eye.